Dtc "C40" (P0505 / P0506 / P0507): Isc Valve Circuit Malfunction - Suzuki VLR1800 Service Manual

DTC "C40" (P0505 / P0506 / P0507): ISC Valve Circuit Malfunction

Detected Condition and Possible Cause
Detected Condition
ISC valve motor current is higher than
H
C40/P0505 the specified value.
L ISC valve motor circuit is open.
Idle speed is lower than the desired
C40/P0506
idle speed.
Idle speed is higher than the desired
idle speed.
C40/P0507
Wiring Diagram
ISC valve
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
18 19 20 21 22 23 18 18
Troubleshooting
CAUTION
!
• Be careful not to disconnect the ISC valve coupler at least 5 seconds after ignition switch is turned
to OFF.
If the ECM coupler is disconnected within 5 seconds after ignition switch is turned to OFF, there is a
possibility of an unusual valve being written in the ECM and causing an error of ISC valve operation.
• When using the multi-circuit tester, do not strongly touch the terminal of the ECM coupler with a
needle pointed tester probe to prevent terminal damage.
NOTE
After repairing the trouble, clear the DTC using SDS tool. Refer to "Use of SDS Diagnosis Reset
Procedures (Page 1A-14)".
12 V
ECM coupler (Harness side)
24 25 26 27 28 29 30 31 32 33 34
Engine General Information and Diagnosis:
Possible Cause
• ISC valve circuit shorted to BATT or ground circuit open.
• ISC valve circuit open or shorted to ground or BATT
circuit open.
• W/Y or Lg wire open or short.
• ISC valve is fixed.
• Air circuit clogged.
• W/Y or Dgr wire open or short.
• Disconnected ISC valve hose.
Lbl
W
Dgr
R/Bl
Lg
35 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51
52 52 52 53 54 55 56 57 58 59 60 61 62 63
1A-80
B822H11104022
ECM
36 IS1A
IS1B
53
35
IS2A
16
BATT
52
IS2B
I822H1110081-02
64 65 66 67 68 68 68
I822H1110010-01